1. Field of the Invention
This invention pertains to the preparation of silane. More particularly it relates to the reaction of a metal hydride with a silicon halide to produce silane and one or more co-products. In a preferred embodiment it relates to the reaction of silicon tetrafluoride with an alkali metal aluminum hydride selected from LiAlH.sub.4, NaAlH.sub.4 and KAlH.sub.4.
Furthermore, this invention relates to a continuous method of preparing silane from a metal hydride and a silicon halide. With the method of this invention, stoichiometric, or substantially stoichiometric operation can be achieved. Furthermore, this invention can produce a fluoride-containing co-product that is free or substantially free of metal hydride starting material. This is an important feature of the invention.
2. Description of the Prior Art
Applicants are unaware of any prior art that describes the continuous, stoichiometric or virtually stoichiometric process described herein, or that describes application of the method to the production of silane from a silicon halide and a metal hydride.
Chemical reactions for the preparation of silane from metal hydrides are known in the art: ##STR1## In addition to the reactions disclosed in the literature cited above, E. M. Marlett (see U.S. Pat. No. 4,632,816, supra) discovered the reaction: ##STR2## In a highly preferred embodiment, the instant invention is applied to enhance the Marlett Process.